Most of this went over my head, but I have a brand new intel core 2 with 4gb of ram, only 3070mb showing in windows. Dell support showed me in the bios that 4gb was there.
The issue is, I also had it installed with Office 2007 and what a memory hog it is! Right now I have Outlook 2007 open, along with a browser and I’m running at 55% of memory used.
I wondered if adding more memory was an option…guess not. 
Good read…thx for the info.
Ron